Theoretical and Empirical Analyses of an Improved Harmony Search Algorithm Based on Differential Mutation Operator

Algorithm 1

Pseudocode of the IHSDE Algorithm.

Procedure IHSDE algorithm

 Initiate_parameters

 Initialize_HM

 While (not_termination)

   For  𝑖=1 to 𝑁 do    //𝑁 denotes the number of decision variables

   if ( rand < HMCR)     //memory consideration

    Select one harmony from HM randomly: 𝑥^new=𝑥^𝑗,𝑗∈𝑈{1,2,…,HMS};

    Execute difference variation operation for the selected harmony:

    𝑥^new_𝑖=𝑥^𝑗_𝑖+𝐹×(𝑥^𝑟1_𝑖−𝑥^𝑟2_𝑖), where 𝐹∼𝑈[0.6,1],𝑟₁,𝑟₂∈𝑈{1,2,…,HMS},𝑗≠𝑟₁≠𝑟₂.

   else

     𝑥^new_𝑖=𝑥_𝑖^𝐿+rand×(𝑥_𝑖^𝑈−𝑥_𝑖^𝐿)   //random selection

   end if

  End for

  Update harmony memory HM     // if applicable

   End while

End procedure